Adjustable tau square



April 8. 1924. 1,489,625

A. BIENERT ET' AL ADJUSTABLE T-SQUAHE Filed'Feb. 17. 1925 Patented Apr. 8, 1924.

UNITED sures ARNOLD IBIENERT AND EnwrN H'AoKEL, or BURGSTEIN, NEAR'I-IAIDA', CZECHO- I PATENT or FICE.

SLOVAKIA.

ADJUSTABLE T SQUARE.

Application filed. February 17, 1923. Serial No. 619,679.

To all whom it may concern:

Beit known that we, ARNOLD BIENERT and EDWIN HACKEL, citizens of the Czechoslovakian Republic, and residing at Burgstein, near Haida, Bohemia, in said Republic, have invented certain new and useful Improvements in an Adjustable T Square, of which the following is a specification.

This invention relates to an improved adjustable T-square, in which not only the blade is adjustable with reference to the head at an angle, but on which, besides, an auxiliary ruler is turnably arranged, which is provided with an arched scale and adapted to be adjusted in axial direction as well as at an angle to the blade of the T-square. Thereby, any angle can be quickly and easily drawn with the aid of the improved T-square without any previous construction or calculation. The working with the aid of the improved T-square takes place in a faultless way and saves much time.

The accompanying drawing shows the improved T-square: Fig. 1 is a plan view of the same, Fig. 2 is a longitudinal section on the line A-B of Fig. 1, Fig. 3 is a cross section on the line CD of Fig. 1, Fig. 4 is a longitudinal section on the line EF of Fig. 1, and Fig. 5 is a plan view of the T-square in the position with adjusted blade and adjusted auxiliary ruler.

On the head a of the T-square, the blade I) v is adjustably mounted by means of a pivot c, a milled-edge nut on the latter serving to fix the two members in any adjusted position. On the blade I) a segment d with a scale thereon is fixed and provided with a slot e in which engages a fixed pin f of the head a. Said pin 7 has a recess 9 and carries on its lower end a blade spring h, which at its upper end has a sharp-edged projection z". The segment d is at the inner side of the slot 9 fitted with a notch k in which engages the projection 73 as soon as the blade 6 lies at right angles to the head a. Said contrivance serves to fix the T-square in its normal rectangular position, so that said position need not at first be adjusted with the aid of the scale on the segment d. Other angular positions of the blade I) to the head a are, however, obtained by means of said scale, in which case the projection z is made to face the respective graduation of said scale, the desired angular position being then fixed by tightening the nut on the pivot c.

'b can be unobstructedly F orbringing the blade 6 into an angular poerably pressed out of the notch k with the thumb of the left hand, though the disengagement of the projection 2' from the notch k takes place automatically by exerting a vigorous pressure on the blade 6 to be adjusted. The pin 7 is provided with a small projectsition to the head a, the projection 11 is prefing pointer f which slides over the graduations of the scale on segment d.

The blade 6 is at its working edge fitted with a metal lining Z, which has a projecting ledge m with a longitudinal slot at therein.

Beneath the blade 6, an auxiliary ruler o is arranged and pivoted to a slide 39 by means of a pin Said slide has a screw-bolt r which passes through the slot 72. and carries a nut s. The slide ;0 can be shifted along the ledge m, the bolt '1" bein then guided in the slot'n. By tightening t e nut s, the slide with the ruler 0 thereon can be fixed in position. The ruler o carries a segmental bow t with an angle graduation thereon. The adjustment takes place in such a way that the graduation of the angle desired coincides with the upper edge of the ledge m.' A clip a embracing the ledge m and engaging in grooves 41 in the underside of the latter as well as in the slot n serves for guiding the segmental bow t.

By means of the ruler 0, lines can be drawn. at any desired angle, the vertex of i which can be brought to the desired point by a corresponding displacement of-the slide p.

In the clip u, furthermore, a set-screw w can be provided in order to fix also the ruler 0 in any desired adjusted position.

When the ruler o is not in use, it lies completely below the ledge m, so that the blade used for drawing lines like with an ordinary T-square.

The metal lining Z protects at the same time the working being damaged.

What we claim, is

An adjustable T-square comprising, in combination, a blade having a longitudinal slot therein, a head pivoted to said blade, a segment with a scale thereon arranged on said blade and having a slot and a notch therein, a pin on said head engaging in said slot, a spring-pressed projection on said pin adapted to engage in said notch, a small pointer on said projection facing said scale, a ledge arranged on the working edge of edge of the blade 6 against said blade, a slide mounted below said ledge and adapted to be adjusted along the latter, an auxiliary ruler pivoted to said slide, a graduated segmental bow provided on said ruler, a bolt on said slide engaging in the longitudinal slot of said blade, a nut on said bolt adapted to fix said slide in any adjusted position, a clip adjustable in the longitudinal slot of said blade and engaging in the underside of said ledge and adapted to guide said segmental bow, and a set-sorew in said clip adapted to fix said segmental bow and thus said auxiliary ruler in any adjusted position, substantially as set forth.

In testimony whereof We ha e hereunto 15 set our hands in the presence of two subscribing Witnesses.

ARNOLD BIENERT. EDWIN HACKEL. \Vitnesses:

AUG. MfiLLER, WAL'IHO SCHULZE. 

